“The president is optimistic, and he needs to be, he’s the guy negotiating, and he needs to make the other side feel like he’s serious about getting something done. But for the rest of us who are watching and know the history of North Korea, we should be skeptical. This is a country that’s made promises before and has broken them, and we’re not talking about promises here regarding minor items. These are nuclear weapons and ballistic missiles that have the capability of reaching the United States,” Rubio said.

Rubio added that if a treaty with North Korea is proposed, the Constitution outlines the necessary role of Congress in that process, which was bypassed in the Obama administration’s Iran deal.

“The reason why the Iran deal was so bad, and frankly unenforceable in the long term, is that it wasn’t a treaty. It was a political agreement that Barack Obama signed onto, and then instead of bringing it to Congress, like our Constitution requires, he just had it ratified by the United Nations.”

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“If we want any sort of deal with North Korea to be enforceable, for the long term, I think it’s actually good for North Korea to have Congress ratify it, because then it becomes a binding treaty,” he said.